Automated progressive ammunition, in particular cartridge, assembly apparatus and method with feedback assembly control

ABSTRACT

The invention relates to an automated progressive ammunition, in particular cartridge, assembly apparatus ( 1 ) and method. The automated progressive ammunition assembly apparatus ( 1 ) according to the invention comprises a conveyor subsystem ( 4 ) and at least one assembly station ( 5 ). The at least one assembly station ( 5 ) comprises an actuator subsystem ( 8 ), a measurement subsystem ( 12 ) and a control subsystem ( 13 ). The conveyor subsystem ( 4 ) is adapted to transport the ammunition ( 2, 3 ) past the at least one assembly station ( 5 ) in an assembly direction ( 6 ) preferably along a rectilinear path. The actuator subsystem ( 8 ) is adapted to move a component ( 9 ), such as a powder or propellant ( 10 ) or a projectile ( 11 ), thereby adding the component to the ammunition. The component thus changes at least one physical parameter (P) of the ammunition. The measurement subsystem ( 12 ) is adapted to measure the at least one physical parameter and output a measurement signal ( 15 ), representative of the at least one physical parameter. In order to be able to meet very tight product specifications, and at the same time allow a quick change between the manufacture of different types of ammunition using the same apparatus ( 1 ), the subsystem ( 21 ) is adapted to control the actuator subsystem ( 8 ) depending on the measurement signal. The at least one assembly station ( 5 ) may, in particular, be a powder filling station ( 18 ) or a projectile insertion station ( 27 ) where powder ( 10 ) or a projectile ( 11 ) is added to the ammunition.

The invention relates to an automated progressive ammunition assembly apparatus and method and in particular to an apparatus and a method for the automated and progressive assembly of cartridges for firearms such as rifles, guns, revolvers and pistols.

For the automated assembly of ammunition, rotatory progressive apparatus are widespread. A rotary progressive apparatus comprises several drums which rotate about their vertical axis. Each drum performs a different assembly step for the ammunition while continuously transporting the ammunition from the previous drum and the previous assembly step to the next drum and the next assembly step. Each drum comprises several almost identical assembly stations which, during the rotation of the drum, each perform in parallel the same assembly step on the various cartridges currently on the drum. EP 112 193 B1 discloses an example of such an apparatus.

BACKGROUND AND STATE OF THE ART

Although these rotatory apparatus are able to produce ammunition at a very high output rate due to their continuous assembly motion, they are cumbersome to adapt to different variants of a cartridge, e.g. to variants which use a different propellant or shell, and even more cumbersome to be adapted to the production of different calibers. In particular, the calibration of the various assembly stations with their many identical substations is very time-consuming.

A different design for an ammunition loading machine has been proposed in U.S. Pat. No. 8,683,906 B2. Here, the working stations are arranged along a line and the cartridges are indexed from station to station by means of a rake assembly. While the apparatus exhibits a more simple construction design the output rate of the single assembly line is limited.

Moreover the production of ammunition is a highly sensitive process in which error prevention and quality control of the products are of great importance.

In US 2014/0260925 A an automated manufacturing system to produce metal case ammunition has been proposed. The system comprises stations for the assembly of the cases, the filling of propellant, the sealing of ammunition and an inspection prior to the sorting and packaging. The inspection of the ammunition is achieved by optical profilometers and line-scan-cameras to assess to correct dimension of the ammunition. Based on the measurements unsuited ammunition can be sorted out. The inspection is however time consuming and allows only for limited estimation of quality of the ammunition.

In U.S. Pat. No. 6,772,668 B2 a reloading machine for used ammunition is disclosed. The machine comprises a detection mechanism in order to check the length of the inserted shells with respect to the length specification of the caliber. In case a deviation from the specified length is determined an alarm is triggered and the process may be stopped. While the detection allows for an error prevention in this regard, the mechanism and apparatus is not suitable for a mass production of ammunition.

The aforementioned U.S. Pat. No. 8,683,906 B2 describes also a sorting mechanism based upon the weighing of the ammunition. In U.S. Pat. No. 8,683,906 B2 the weight of the cartridges is measured prior to the filling of propellant and the insertion of a projectile as well as after these steps. The machine thus allows for a comparison of the weight of an empty shells with the completed cartridges. In case of deviations from a pre-set tolerance band the cartridges are ejected from the machine. The mechanism allows for a rough control quality control, but not of a precise monitoring of single assembly steps. Moreover the ejected cartridges may be not reused, leading to a reduced product yield.

While in the state of the art some mechanisms for error prevention and quality control in the process of ammunition production have been proposed. These systems exhibit limitations in terms of output rates, product specifications as well as process efficiency and flexibility.

It is therefore an objective of the present invention to provide an ammunition assembly apparatus that overcomes the disadvantages of the prior art. In particular it is an objective to improve an automated progressive ammunition assembly apparatus and method so that the effort and the downtimes for meeting the specifications of a particular type or variant of ammunition are reduced.

For an automated progressive ammunition, in particular cartridge, assembly apparatus, this objective is achieved in that the apparatus comprises a conveyor subsystem and at least one assembly station, the at least one assembly station comprising an actuator subsystem, a measurement subsystem and a control subsystem, the conveyor subsystem being adapted to transport ammunition past the at least one assembly station in an assembly direction, the actuator subsystem being adapted to add a component, such as a propellant or a projectile, to the ammunition, the component changing at least one physical parameter of the ammunition, the measurement subsystem being adapted to measure the at least one physical parameter and output a measurement signal representative of the at least one measured physical parameter, wherein the control subsystem is adapted to control the actuator subsystem depending on the measurement signal.

For the automated progressive ammunition, in particular cartridge, assembly method, this object is solved by comprising the steps of adding a component to the ammunition, thereby changing a physical parameter of the ammunition, of automatically measuring the physical parameter, and of automatically modifying the addition of the component depending on the measured physical parameter.

The known rotatory apparatus have to be operated in an open-loop control mode. Operational parameters are preset manually and maintained constant by the apparatus. Samples are also controlled manually and deviations from the operational parameters are compensated again manually by adjusting the setting.

In contrast, the apparatus according to the invention uses feedback control to constantly control the motion of the actuator during the manufacturing process. This results in a more reliable operation of the apparatus with less downtime. Changes and shifts of operational parameters of the assembly apparatus which may occur over long periods of operation are automatically compensated without any further human interaction.

Starting from this concept of the invention, the following aspects further improve the operation of the apparatus and method according to the invention independently of one another. The various aspects described below can be combined independent of each other depending on the needs of a specific application of the apparatus and method.

For example, the conveyor subsystem may comprise a linear section, along which the assembly stations are arranged one behind the other in the assembly direction, preferably in a straight line. Such a linearly arranged assembly system is more easily maintained and adapted than a tightly packed rotary system. Further, the conveyor subsystem may comprise a conveyor belt and a drive, the drive being adapted to intermittently move the conveyor past a series of subsystems of one or more assembly stations.

According to another embodiment the whole apparatus may have a linear plan, with all components being arranged serially in the assembly direction, preferably without any overlap. Preferably, there is only a single instance of each particular assembly station comprised in the apparatus. This single instance performs its assembly step on each cartridge in the apparatus. Not using a plurality of parallel assembly stations for each particular assembly step, such as in rotatory assembly apparatuses, facilitates the feedback control. It also reduces the costs both for retooling and for maintenance of the apparatus.

With a linear, in particular rectilinear, setup, the apparatus is easily scalable both with regard to output rate as with regard to versatility. For example, two apparatuses can be placed side-by-side on a common machine base to form an automated progressive ammunition assembly system with a doubled output or with the possibility to manufacture two variants of the same cartridge or of two different cartridges side-by-side. Two neighboring apparatuses may share a common reservoir of at least one component which is added during the operation of each of the apparatuses. For example, two apparatuses arranged in parallel may have the same powder reservoir but have different reservoirs for the shells and/or the projectiles.

In order to keep the conveyor subsystem cost-efficient and simple to maintain, the conveyor belt may be an endless belt which comprises niche-like compartments for receiving the shells or cartridges. Preferably, each compartment receives a single round of ammunition. The conveyor belt may have the shape of a toothed belt, the space between two adjacent teeth being used as a compartment.

The conveyor belt may transport each round of ammunition in a standing position. In particular, each cartridge or shell may slide on a stationary transport plane of the apparatus. The transport plane may be made of polished and, in particular, hardened steel. The transport plane may be formed by a metal strip which is adapted to be removed if worn out. The metal strip may have a L- or U-shaped cross-section to provide lateral support with its legs for the belt and/or the cartridge within the compartments, while the cartridges may rest on its bottom. Thus a transport channel may be formed by the slider bar and the retainer bar. The cartridges are moved by the belt through the transport channel.

The inner width of each compartment may be larger than the outer width, in particular the maximum outer width, of the cartridges which are currently manufactured. Thus, the cartridge is not clamped or in any other way restricted or fixed by the compartment, but simply received in the compartment and being pushed for transportation by the compartment. In this configuration, the cartridges are received loosely within their respective compartment. In particular, the cartridges may be fed into a compartment and removed from a compartment simply by gravitation, e.g. by falling into and/or out of a compartment.

According to another embodiment, the compartments of the conveyor belt may surround the respective cartridge on only three sides and may be open laterally, i.e. in a direction perpendicular to the assembly direction and parallel to the transport plane.

The open side of the compartments may be covered by a stationary retainer bar which runs parallel to the conveyor belt at least in that section of the conveyor belt, where the rounds of ammunition are being worked on. The retainer bar keeps the cartridges in the compartments.

Preferably, there is no physical contact between the conveyor belt and the retainer to keep the friction low. The retainer bar should not exert any pressure on the cartridges in the compartments to keep the friction during transport low. The retainer bar may be combined with the slider bar to a U- or L-shaped bar.

In a return section of the conveyor belt, neither a strip for the transport plane nor a retainer bar is needed.

The conveyor belt is preferably endless and wound about at least two pulleys, the axes of which are preferably perpendicular to the transport plane, i.e. the axes of the pulleys may be aligned with the axis of the rounds transported standing up.

Preferably, the conveyor subsystem transports the cartridges intermittently by alternating between a working cycle, where the cartridges are not moved and being worked upon, and a transport cycle, in which the cartridges are transported. The length of the working cycle and the transport cycle re-mains constant at least for the same type of cartridges.

In contrast to a rotatory ammunition assembly apparatus, the at least one assembly station of the ammunition assembly apparatus according to the invention is preferably stationary and does not move with the ammunition which is transported through the apparatus.

The apparatus according to the invention is especially suited to process shells which may have already been provided with a primer, and need to be provided with a propellant, such as powder, and/or a projectile.

The at least one assembly station, which is controlled depending on the measurement signal, may be a powder filling station.

The component added to the shell to produce the cartridge by the actuator subsystem may be the propellant such as powder. In this case, the at least one physical parameter is powder weight, i.e. the actual weight of the powder in the cartridge.

If the physical parameter to be measured by the measurement subsystem is the actual weight of the component added by the actuator subsystem, it is preferred that the measurement subsystem comprises a net weighing apparatus which is arranged in the assembly direction before the actuator subsystem, and a gross weighing apparatus which is arranged in the assembly direction behind the actuator subsystem. It is preferred that the net and gross weighing apparatuses are arranged immediately before and immediately behind the actuator subsystem and that no further operations than the one performed by the actuator subsystem are performed on the cartridges between the net and the gross weighing apparatus. This avoids compromising the results of the weight measurements. The actual weight of the added component can be deduced accurately from subtracting the net weight measured by the net weighing apparatus from the gross weight measured by the gross weighing apparatus. The measurement signal in this case may correspond to this difference.

The net weighing apparatus and the gross weighing apparatus may be identically configured.

The measurement subsystem in another embodiment may comprise a weighing apparatus which has a weighing cell, which is aligned with the conveyor subsystem, in particular the compartments of the conveyor belt. In one embodiment, the weighing apparatus is adapted to measure the weight of the cartridges without removing the cartridges from their respective compartments.

For example, the weighing cell may be mounted flush with the transport plane of the conveyor sub-system. In operation of the automated progressive ammunition assembly apparatus, the cartridges may simply be pushed by the conveyor subsystem from the transport plane onto the weighing cell. For this, the weighing cell should be vertically aligned with a resting position of the conveyor subsystem, where, in each working cycle, a compartment comes to rest.

In order to avoid that the weight measurement is distorted by a physical contact between the cartridge on the weighing cell and the conveyor subsystem, the weighing cell may be provided with a centering apparatus. The centering apparatus may be adapted to automatically move the ammunition away from contact with the conveyor subsystem upon transport onto the weighing cell, in particular within the time frame of a transport cycle.

For increased longevity and reliability, the centering apparatus may be a purely mechanical device which is adapted to be passively activated or operated by the conveying motion of the conveyor subsystem. By being passive, no actuator using external energy is needed for moving the ammunition away from contact with a conveyor subsystem.

The release of any contact between the ammunition on the weighing cell and the conveyor subsystem without removal of the ammunition from the conveyor subsystem is facilitated if the ammunition is received loosely in a compartment of the conveyor subsystem. In this embodiment, a simple centering of the ammunition within the compartment keeps the ammunition and the compartment limits spaced apart from each other. The centering mechanism should be part of the weighing cell in order not to influence the measurement.

In a specific embodiment of the centering apparatus, a spring drive may be provided with at least one centering bevel. The centering bevel may provide a self-centering seat for the cartridge which automatically centers the cartridge with respect to the assembly direction. The spring drive may be adapted to be automatically loaded by the cartridge transported by the conveyor onto the weighing cell. If the ammunition is in the position ready to be weighed, the ammunition is fully received in the at least one centering bevel. The centering bevel may be arranged on a spring arm that is adapted to be deflected by a cartridge entering and/or leaving the centering bevel.

The centering bevel may be a V- or U-shaped recess or cut-out with its bottom, i.e. the position of the maximum inner width, being aligned with the center of the weighing cell. Due to the spring action of the spring drive, the cartridge is automatically transported towards and held in the bottom of the bevel once it has entered the centering bevel. Thus, the ammunition automatically clips into the spring drive during the transport cycle and is centered in the course of the clipping motion. In the next transport cycle, the ammunition is pushed out of the centering mechanism, again, preferably by simply prying the spring arms apart.

The spring drive may comprise one or two pairs of opposite spring arms, wherein at least one arm of a pair is provided with the centering bevel. One pair may be located at the height of a neck of the cartridge, another pair at the height of the base of the cartridge.

Upon being pushed onto the weighing cell, the at least one pair of spring arms is pried apart until the bevel is reached and the cartridge is moved by the spring force along the bevel.

In a further preferred embodiment of the invention the automated progressive ammunition assembly apparatus is characterized in that the measurement subsystem comprises a weighing apparatus comprising a weighing cell and the apparatus comprises a transport device adapted to separate the cartridges from the conveyor subsystem in order to pass them onto the weighing cell.

In this preferred embodiment the weighing cell is not installed in line with the preferably at least sectionwise linear conveyor subsystem, but the weighing cells is positioned outside the conveyor subsystem. The separation of the cartridges from the conveyor subsystem towards a weighing cell is preferably understood to refer to a transport step of taking the cartridges out of the conveyor subsystem, e.g. the compartments of the conveyor belt. Preferably the compartments of the conveyor belt are shaped such that the shells or cartridges transported therein have a minimal amount of play (gap) in order to ensure a precise alignment for the different assembly steps. However during the weighing procedure a contact of the cartridges with the conveyor belt should be avoided. As described above, in one embodiment this may be achieved by a centering apparatus while the cartridges may remain in the compartments. However, in order to further improve the accuracy of the weight determination it is particularly advantageous to take the cartridges out of the compartments of the conveyor belt and transfer them to a weighing apparatus separated and aside from the conveyor belt. This embodiment proved to be particularly suited to yield precise measurements of the ammunition powder and to avoid any factors potentially comprising such measurements as e.g. the transmission of vibrations for the conveyor subsystem to the weighing cells.

In a further preferred embodiment of the invention the automated progressive ammunition assembly apparatus is characterized in that the conveyor subsystem comprises a conveyor belt configured to transport the ammunition within compartments and the transport device comprises at least one transport wheel adapted to receive the ammunition from said compartments and transport the ammunition onto the weighing cell.

In the preferred embodiment the shells or cartridges are transported within compartments by means of the conveyor belt towards the rotatable transportation device configured to take the cartridges out of the conveyor belt, place them onto the weighing apparatus and replace the cartridges back into the conveyor belt. To this end the transportation device comprises at least one rotatable transport wheel shaped to receive the ammunition in compartments or niches and move the ammunition on a circular transport plane towards the weighing cell. In order to arrive at a higher stability it may also be preferred to use two transportation wheels to this end. Preferably the transportation wheels can be automatically rotated, e.g. by means of a servo motor, such that the rotation is synchronized with the movement of the conveyor subsystem. As described above, it is preferred that the conveyor subsystem transports the cartridges intermittently by moving the cartridges during a transport cycle and working on still standing cartridges during a working cycle. Likewise the rotation of the transportation wheel is thus preferably intermittent and moves the cartridges in a step-wise fashion towards the weighing cell. Moreover it is important to note that the weight measurements are taken during the working cycle of the transportation wheel, thus during a resting time in which the cartridges are not being moved, but are standing still on the weighing cells. In comparison to weight measurements taken of moving cartridges the preferred weight measurement is characterized by a superior precision.

It is particularly preferred that the weighing cell is not mechanically connected to the conveyor subsystem. For instance the conveyor subsystem may be mounted to a base frame or mounting plane, while the weighing cell is situated on top of a mechanically independent socket. It is preferred to install the net weighing and gross weighing apparatus together, e.g. on a separate socket, and position the actuator subsystem of the powder filling station such that ammunition powder may be added to the cartridge in between the net weighing and gross weighing apparatus. Thereby the transportation device may successively pass the cartridges through the net weighing apparatus, the powder filling subsystem, the gross weighing apparatus and back into the conveyor belt. The operation of such a rotatable transportation device allows for a particularly synchronized and secure measurement mechanism.

Moreover after a transportation cycle, i.e. after moving a cartridge onto a weighing cell, it is particularly preferred that the transportation device is configured to perform a substep reverse rotation. The substep reverse rotation preferably refers to a slight backwards rotation of the transportation wheel of substantially less, e.g. less than ¼^(th), than the length of a transport cycle. It is particularly preferred to perform a reverse rotation that yields a minimal distance between 0.5 mm and 1 mm between the shell and the compartment of the transport device.

Due to this movement the shell advantageously ceases to contact the transportation wheel, while standing on the weighing cell. Said mechanism allows for a particular efficient decoupling of weighing apparatus from the conveyor subsystem or other components that may induce vibrations.

In the powder filling station, the actuator subsystem is adapted to fill the powder into the shell. To this end, the actuator subsystem may comprise a dosing mechanism which is adapted to separate a portioned dose of propellant from a propellant reservoir and to move the apportioned amount into the shell. In particular, the dosing may comprise a threaded arbor. The number of revolutions of the arbor determines the amount of powder moved into the shell. The dosing mechanism is operated intermittently in synchronization with the transport and/or working cycle of the conveyor subsystem.

The assembly station, in this case the powder filling station, may also be provided with a control subsystem which is adapted to control the actuator subsystem. For example, the control subsystem of the powder filling station may control the operation of the dosing mechanism. This can be done by controlling the number of revolutions of the arbor. If the amount of powder in a cartridge needs to be changed, the amount of revolutions of the arbor is changed accordingly.

According to one embodiment of the invention, the operation of the dosing mechanism is controlled in dependence of the actual powder weight in the cartridge, or a signal representative of the actual powder weight, as determined by the joint operation of the net and the gross weighing apparatus.

The control subsystem may be provided with a storage member which is adapted to retain a target value for the physical parameter to be maintained by the assembly station. In the powder filling station, the target value may be the powder weight in a cartridge as defined by the specification for that particular cartridge or by ballistic tests which are carried out with samples from the ongoing production process.

The action of the dosing mechanism may thus be adjusted by a difference between the actual weight of the powder in the cartridge and the target value. If the actual weight is too low, the amount of powder provided by the dosing mechanism is increased; if the actual weight is too high, the amount of powder provided by the dosing mechanism is decreased.

In a further embodiment it may be preferred to produce an initial set of sample ammunition, e.g. a a series of 20 or less cartridges, at a slower operation speed in order to allow for precise initial fine tuning of the actuator subsystem, e.g. dosing mechanism. Once the feedback control achieves a state in which the actual weight of powder in the cartridges robustly matches the target weight, the speed for the ammunition assembly is increased. By operating the apparatus at a slower initial output rate to fine tune the actuator subsystems less ammunition has to be rejected in the initial calibration phase.

The loose reception of the cartridge within a compartment and the upright transport of the cartridge may require a special configuration of the powder filling station, in particular its actuator subsystem, to avoid the spilling of powder. For example, the actuator subsystem may comprise two hollow concentric tubes, which are brought into abutment with the shell currently underneath the actuator subsystem in the working cycle.

An outer hollow tube may be a centering tube with an inner bevel. The centering tube, respectively its inner bevel, is brought into mechanical contact with the shell, either a shoulder at the outer periphery of the shell or, preferably, with the upper rim of the shell. The bevel is dimensioned so that its peripheral surface comes to rest against the shell and thereby automatically centers the shell.

An inner tube may be a feeder tube through which the propellant is guided into the shell. The feeder tube may be rigidly connected to the centering tube or may be driven independently of the feeder tube along the common axis.

The at least one assembly station may be a projectile insertion station which may be used in the apparatus and/or method in addition to a powder filling station as described above or any other kind of assembly station. The at least one physical parameter in the case of a projectile insertion station may be the length of the cartridge including the inserted projectile.

At the projectile insertion station, the projectile may be pressed into the shell using a press-in tool that may be moved from above onto the projectile of the standing shell. The length of the cartridge is determined by the end position of the press-in tool, preferably after applying a determined press-in force acting in the longitudinal direction of the shell against the projectile.

If the at least one physical parameter to be determined by the measurement subsystem is the length of the cartridge, the measurement subsystem may employ a measurement apparatus which is brought into contact with the tip of the cartridge.

For instance the length measurement apparatus may comprise a guiding tube with a measurement pin. To measure the length of the cartridge the cartridge may be positioned underneath the guiding tube, which is lowered until coming to abut the cartridge. The length of the hence positioned cartridge may be determined by measuring the translation of the measurement pin until the pin contacts the tip of the cartridge, i.e. the tip of the projectile. Such a mechanical mechanism for the detection of the cartridge length may be preferred. However other detection means such as optical detectors are equally possible. The length measurement apparatus is preferably installed along the assembly direction behind the actuator subsystem for the insertion of the projectiles.

A control subsystem of the projectile insertion station may be adapted to compare the actual length of the cartridge thus determined to a target length stored within the control subsystem. Depending on a deviation of the actual length from the target length, a maximum stroke and/or a maximum insertion force of the actuator subsystem, which is adapted to press the projectile into the shell, may be adjusted automatically during operation of the apparatus.

Using the at least one physical parameter such as the actual powder weight for controlling a powder filling station and/or the actual cartridge length for controlling a projectile insertion station, the apparatus constantly adapts the apportioning of the powder and/or a pressure and/or a stroke with which the projectile is pressed into the cartridge in a feedback-loop.

According to another embodiment, another length measurement subsystem may be used in an assembly direction behind a crimping station, where the shell is crimped onto the projectile. The crimping station may be adapted to adjust the crimping process depending on the measured length of the cartridge after crimping.

Preferably, the storage section of the control subsystem is adapted to permanently store the latest adjustment value for the actuator subsystem, such as the latest deviation of the measured physical parameter from the stored target value. It is of advantage if the adjustment value is associated in the storage section to a respective cartridge type for which the adjustment value was calculated.

In particular, the control subsystem may be adapted to retain an array of such values and their type of cartridge associated with these values. Thus, if the assembly station is used to manufacture a new type or variant of cartridge, the latest adjustment for the previous type of cartridge is stored. If production of the previous type of cartridge is resumed, the stored adjustment value may be used as an initial value to start the manufacturing of the previous type of cartridge. This ensures a fast convergence to the desired value of the physical parameter in the new manufacturing process.

Preferably, the at least one physical parameter of the actual cartridge is not determined by a single momentary measurement value but by a sliding average of a plurality of subsequent momentary values such as in the order of 100, 1,000, 20,000 or more subsequent values. A large number of samples contributing to the measurement value decreases the influence of rogue results, which e.g. a large powder flake or a singular deformed projectile may present, on the overall manufacturing process.

The apparatus may, in another embodiment, also be provided with a control and storage section which is adapted to keep track of selected physical properties of all individual cartridges currently transported by the conveyor subsystem. For this, the control and storage section is adapted to store an image of the ongoing manufacturing process in memory, in which image each cartridge is assigned at least one of a position in the assembly direction, an ID number, a physical parameter, and a reject flag.

As described above the weight of the cartridges can be preferably measured by a weighing apparatus, while the length of the cartridge by a cartridge length measurement apparatus. The measured parameters are compared with pre-set tolerances ranges for each of the physical parameters. Cartridges for which the measured physical parameters are outside the preset tolerance ranges do not meet the specification and are marked by a reject flag.

Thus, the control and storage section may be adapted to keep track of a cartridge which has been marked as a reject. This may eliminate the need of a plurality of individual reject stations along the assembly direction which remove reject cartridges from the conveyor subsystem behind each assembly station. By being able to keep track which cartridge is a reject, only a single reject station is needed at the end of the assembly line.

Suited cartridges, i.e. cartridges not marked by a reject flag, preferably pass said reject station to be moved on to collector container, while unsuited cartridges, i.e. cartridges marked by a reject flag, are sorted towards a waste container.

The control and storage section may be further adapted to mark, in its memory, cartridges for special treatments such as blank cartridges and to control the stations along the conveyor belt accordingly.

The extraction of either a cartridge from the conveyor subsystem may be facilitated if the cartridge is held loosely in the conveyor subsystem and is transported standing up on a stationary transporting plane. For ejecting a cartridge, an opening in the transport plane may be provided. As the cartridge is held only loosely, it will automatically fall through the opening once it is pushed over the opening during the transport cycle.

For a reject opening, a closure mechanism such as an actuator-controlled flap or blind may be used. The closure may only be activated if a cartridge marked as reject in the control and storage section of the apparatus is transported onto the opening.

According to another preferred embodiment, the automated progressive ammunition assembly apparatus is provided with a horizontal bulkhead which serves as a preferably dust-tight barrier to prevent the propellant or powder from falling into lower parts of the apparatus. The horizontal bulkhead thus divides the apparatus into a, preferably upper, manufacturing space in which the conveyor subsystem and the at least one assembly station as well as the measurement subsystems and the reservoirs for the components are located, and a, preferably lower, bottom space. The bottom space may be adapted to receive supply equipment, such as electric supply units. The horizontal bulkhead may form a massive seal between the manufacturing space and at least one bottom space beneath the horizontal bulkhead. The bulkhead is preferably located below the transport plane. At least some subsystems may be mounted to the frame of the assembly apparatus to be spaced apart from the bulkhead. E.g. the subsystems may be mounted at a mounting plane of the assembly apparatus. The transport plane may be spaced apart from the bulkhead. Thus, all machinery is located in a distance above the bulkhead. Any propellant falling down from the subsystems falls onto the bulkhead where it is clearly visible. The horizontal bulkhead may be made from metal to avoid static discharges.

Preferably, there are no unsealed openings in the horizontal bulkhead which connect the manufacturing volume to the at least one bottom space.

Preferably, the conveyor subsystem and each assembly station are located above the horizontal bulkhead, preferably with empty space between them and the bulkhead. The only exception may be the weighing apparatus, where the weighing cell may be at least partly located beneath the mechanical bulkhead and be provided with a base separate from the base of the remaining apparatus to decouple any vibrations from the conveyor subsystem.

In a preferred embodiment of the invention the automated progressive ammunition, in particular cartridge, assembly apparatus is characterized in that the apparatus comprises a mounting plane to which the at least one assembly station and the conveyer subsystem are attached such that the conveyer subsystem and the at least one assembly station are situated above the horizontal bulk head and an empty space remains between the conveyer subsystem the at least one assembly station and the surface of the horizontal bulk head. It may be particularly preferred that the mounting plane forms together with the bulkhead an L-shaped support for the conveyer subsystem and the at least one assembly station. By attaching the conveyer subsystem and the at least one assembly station to the mounting plane of the apparatus, advantageously an empty space is formed between the transport plane of the cartridges or shells and the upper surface of the bulkhead. The empty space may be advantageously adapted by altering the attachment of the conveyer subsystem and the assembly station to the mounting plane. The empty space allows for a good accessibility and in particular for a fast and efficient cleaning of the bulkhead surface, enabling an easy removal misplaced ammunition powder from the apparatus. Moreover the formed empty space minimizes vibrations between the rotating conveyer belt and the assembly stations, thereby augmenting the stability of the apparatus while operating.

Moreover the attachment of the assembly stations to the mounting plane allows for a modular design of the ammunition assembly apparatus. In particular in this preferred embodiment assembly stations may be easily mounted onto or removed from the ammunition assembly apparatus. For instance an ammunition assembly apparatus may comprise two assembly stations, which are a powder filling station and a projectile injection station. This may constitute a minimal ammunition assembly apparatus station. If for instance for certain applications a crimp station is necessary, the crimp station may be readily mounted onto the mounting plane behind the projectile injection station in a direction along the assembly line. Likewise certain subunits or elements of assembly stations may be easily exchanged in the preferred modular embodiment.

In a preferred embodiment of the invention the automated progressive ammunition, in particular cartridge, assembly apparatus is characterized in that the conveyer subsystem comprises a plurality of assembly stations, wherein the conveyor subsystem extends linearly at least sectionwise through the automated progressive ammunition assembly apparatus and the assembly stations are arranged rectilinearly one behind the other in the assembly direction.

The at least sectionwise arrangement of the conveyer subsystem, preferably the conveyer belt, and the rectilinearly arrangement of the assembly stations leads to a particular space efficient arrangement of the apparatus. Moreover due to the rectilinear arrangement of the assembly stations a dense operation on the cartridges can be achieved leading to a high productivity.

In a further preferred embodiment the invention relates to an automated progressive ammunition assembly system comprising at least two automated progressive ammunition assembly apparatus, wherein the least two apparatus are attached to the same side of the mounting plane and arranged parallel and side-by-side. Moreover it may be preferred that the apparatus share at least one reservoir for instance for the ammunition powder or the shells thereby allowing for a cost efficient use of the construction elements.

In a further preferred embodiment the invention relates to an automated progressive ammunition assembly system comprising at least two automated progressive ammunition assembly apparatus, wherein a first of the two apparatus is attached on one side of the mounting plane, while a second of the two apparatus is attached on the opposite side of the mounting plane. To this end it is preferred that the mounting plane and the horizontal bulk head form a T-shaped support for the assembly system. It may further be preferred that on each side of the mounting plane two or ammunition assembly apparatus are arranged parallel and side-by-side. It was surprising that such a compact construction of a system for the assembly of ammunition is possible and allows for an augmented productivity in comparison to the prior art.

Moreover due to the modular design that arises from the attachment of the assembly stations to the mounting plane, the preferred system allows for a particular high flexibility. For instance different assembly stations may be mounted upon the system on each side for the manufacturing of different ammunitions. Advantageously it is thus possible to manufacture different types of ammunition and/or caliber using the same system. In the preferred embodiment each apparatus of the system can be controlled and adapted independently. Moreover it is possible for instance to repair, clean and/or reassemble the at least one apparatus, which is on one side of the mounting plane, while the at least one other apparatus, which is on the other side of the mounting plane is continuing to produce ammunition. Production downtimes are therefore reduced.

In a further preferred embodiment the invention relates to an automated progressive ammunition, in particular cartridge, assembly method comprising the steps of adding a component to the ammunition thereby changing a physical parameter of the ammunition, of automatically measuring the physical parameter and of automatically modifying the addition of the component depending on the measured physical parameter.

A person skilled in the art appreciates that the method according to the invention is preferably carried out using an automated progressive ammunition assembly apparatus according to the invention or preferred embodiments thereof. Preferred embodiments, technical features and advantages disclosed for the apparatus according to the apparatus equally apply to the method according to the invention. For instance a preferred apparatus according to the invention comprises weighing apparatus to determine the net and gross weight of the shells prior and after the filling with ammunition powder in order to deduce the weight of said powder. Based upon the measurement it is further preferred that a control subsystem adapts the amount of ammunition powder added to the shells. A person skilled in the art thus understands that for the method according to the invention likewise it is preferred to measure the powder weight, by a weight measurement of the shells prior and after the filling and to automatically modify the addition of the powder based upon said measurement.

In the following, the invention is exemplarily described with reference to the drawings. In the drawings, the same reference numeral is used for elements which correspond to each other in their design and/or their function.

Moreover, it is clear from the above description of the various advantageous embodiments, that the combination of features shown in the drawings and explained below may be changed depending on the specific application at hand. For example, a feature not shown in the drawings but mentioned above may be added if the technical effect of this feature is required for the specific application. Conversely, a feature shown in the drawings may be omitted, if its technical effect is not needed for the specific application.

In the drawings:

FIG. 1 shows a schematic representation of an automated progressive ammunition assembly apparatus and method according to the invention;

FIG. 2 shows a schematic perspective view of a preferred embodiment of an automated progressive ammunition assembly apparatus according to the invention;

FIG. 3 shows a schematic view of a detail of FIG. 2;

FIGS. 4 to 6 show schematic views of a preferred measurement subsystem for measuring the weight of a cartridge according to the apparatus and method according to the invention;

FIG. 7 shows a schematic perspective view of a powder filling station according to the invention;

FIG. 8 shows a schematic perspective view of a system which comprises two apparatus according to the invention;

FIG. 9 shows a schematic representation of a preferred embodiment of an apparatus according to the invention, wherein the assembly stations and the conveyer system are attached to the mounting plane; and

FIG. 10 shows a schematic view of a further preferred measurement subsystem for measuring the weight of a cartridge comprising a rotatable transport device

First, the basic design and function of an automated progressive ammunition assembly apparatus 1, according to the invention, is explained with reference to FIG. 1. In FIG. 1, each step carried out by the apparatus 1 is represented by a block. As each step is carried out by a specific dedicated structure of the apparatus 1, the blocks of FIG. 1 also schematically represent the structural outline of the apparatus 1.

The apparatus 1 as shown uses shells 2 to produce cartridges 3. To this end the shells 2 are filled with a propellant, i.e. ammunition powder, and a projectile 11. Commonly the end products, i.e. shells 2 comprising the propellant and the projectile 11, are referred to as cartridges 3. However in the context of the invention shells may also be referred to as cartridges, which are not fully assembled. For the sake of simplicity the terms shells and cartridges are therefore preferably used synonymously, except where a clear differentiation seems to be more appropriate.

In the embodiment shown, the apparatus 1 comprises a conveyor subsystem 4, which is schematically represented by the arrows between the blocks.

The conveyor subsystem 4 linearly transports shells 2 and cartridges 3 from one assembly station 5 to the next. At each station 5, a single manufacturing and/or control step is performed on the shell 2 or the cartridge 3.

The conveyor subsystem 4 is adapted to move linearly, i.e. in a straight line from one assembly station 5 to the next. Thus, the assembly stations 5 are lined up linearly in an assembly direction 6, in which the cartridges 3 are transported. The conveyor subsystem 4 is adapted to move intermittently between the stations by switching between a transport cycle, in which the cartridges 3 are moved, and a working cycle, in which the cartridges 3 rest and are being worked upon. The transport and the working cycle are constant throughout the manufacturing process of at least one variant or type of cartridge 3. The assembly stations 5 are spaced apart from each other in the assembly direction 6 in an integer multiple of the step width of the transport cycle.

Each assembly station 5 may comprise several subsystems. One such subsystem may be an actuator subsystem 8, which performs a particular assembly step e.g. by adding a component 9, such as a propellant or powder 10 or a projectile 11, to a cartridge 3.

The assembly station 5 may further be provided with a measurement subsystem 12, which may measure a physical parameter P of the cartridge 3 such as a weight W or a length L, which has been changed due to the addition of the component 9.

Furthermore, an assembly station 5 may comprise a control subsystem 13 which is adapted to control the actuator subsystem 8, in particular an actuator 14 thereof, which performs a movement by which the component 9 is added to a cartridge 3.

A measurement signal 15 may be input to the control subsystem 13 from the measurement subsys-tem 12. The control subsystem 12 may be adapted to control the actuator subsystem 8 depending on the measurement signal 15. The measurement signal 15 may be an analog or digital representation of the physical parameter P.

In the embodiment shown in FIG. 1, the first assembly station 5 is a powder filling station 18, in which powder 10 is filled into the cartridge 3. This step is carried out in a filler subsystem 19.

Typically, the cartridge 3 has to satisfy very tight specifications. A cartridge which does not meet the specifications is a reject. For example, the weight W of the propellant 10 in the cartridge has to be within ±15 mg for a 7.62 mm NATO cartridge. Cartridges 3 with too much or too few powder may not be used. The exact amount of propellant 10 is determined by the gas pressure which is to be generated in the chamber. The gas pressure not only depends on the amount of powder in the shell but also on the quality and granularity of the powder. Thus, the manufactured cartridges need to be controlled continuously during the manufacturing process by ballistic tests of production samples.

To maintain an exact filling of powder throughout the manufacturing process even over very long production periods, the powder filling station 18 comprises a measurement subsystem 12, which is adapted to measure the weight W of the propellant 10, which has been added as the new component 9 by the powder filling station 18. The measurement subsystem 12 of the powder filling station 18 comprises a net weighing apparatus 20 a and a gross weighing apparatus 20 b. The net weighing apparatus 20 a is arranged in the assembly direction 6 before an actuator subsystem 8, which performs the actual filling of the propellant 10 into the shell 2. In the powder filling station 18, the actuator subsystem 8 comprises as an actuator 14 a dosing mechanism 21 for apportioning the powder and delivering it into the shell 2.

The gross weighing apparatus 20 b is arranged in the assembly direction 6 preferably immediately behind the actuator subsystem 8.

In operation, the net weighing apparatus 20 a determines a weight W_(N) of the shell 2 before the powder filling, and the gross weighing apparatus 20 b determines a weight W_(G) of the shell 2 after the powder filling. The difference W_(G)-W_(N) of the two weight measurements W_(G), W_(N) by the net and gross weighing apparatus 20 a, 20 b yields the actual weight of the powder 10 in the cartridge.

The control subsystem 13 of the powder filling station 18 is adapted to control the dosing operation of the dosing mechanism 21 depending on the measurement signal 15.

The measurement signal 15 may reflect a single momentary measurement value or an average of a plurality of subsequent or randomly picked momentary measurement values, as e.g. calculated using a sliding average. The amount of samples used for the sliding average may vary e.g. between 100 and 10,000. This results in a comparatively short time window, over which the average is calculated, given that an apparatus according to the invention may assemble between approximately 120 and 200 rounds of ammunition per minute.

More specifically, a storage member 22 may be provided in the control subsystem 13 which retains a representation of a target value T of the particular physical parameter P determined by the measurement subsystem 13. The target value T corresponds to the value of the physical parameter P as prescribed by the specification for the cartridges 3. The storage member 22 may be any one of a digital or analog electric or electronic memory, or a mechanic device such as a manipulator which is mechanically set to a certain position which represents the target value T.

In the case of the powder filling station 18, the storage member 22 may store a target weight W_(T) for the powder in the shell as target value T. This target value T can be manually varied during the manufacturing process. For example, ballistic tests of sample products may necessitate a change of the target powder weight W_(T) in order to maintain the specified gas pressure of the cartridge 3.

The deviation W_(T)-(W_(G)-W_(N)) of the powder in a single shell from the target value W_(T) or, if a sliding average is used, the average actual deviation

$\sum\limits_{n = 1}^{N}\frac{W_{T} - \left( {W_{G} - W_{N}} \right)}{N}$

of N previous shells 2 is used by the actuator subsystem 8 to compensate the deviation. This can be done by a simple PID-control algorithm or any other control algorithm.

A reject station 23 may be arranged in the assembly direction 6 behind the assembly station 18 to remove reject cartridges which do not fulfill the specifications from the assembly process.

However, it is preferred that a storage and control subsystem 24 of the apparatus maintains a memory representation 26 of preferably all the cartridges currently being transported by the conveyor subsystem 4. In the memory representation, an ID, at least one physical property P, a reject flag R and/or its position in the apparatus 1 may be assigned to a particular cartridge 3. The handling of a particular cartridge 3 may depend on one or more of the values of in the representation 26.

For example, if a measurement subsystem 13 measures a physical parameter P which lies outside the specification, the respective cartridge 3 may be marked as a reject by setting the reject flag R and be ejected at the end of the assembly. The apparatus 1 may be adapted to not perform any operation on a cartridge 3 which is marked as reject. Further, the representation 26 of the array of cartridges in the conveyor subsystem 4 may mark specific types of cartridges, such as blanks which have been deliberately manufactured but for which some subsequent assembly steps, such as projectile insertion or crimping, need not be carried out or need to be carried out differently.

In addition to or alternatively to the powder filling station 18, the apparatus 1 may comprise a projectile insertion station 27 as an assembly station 5.

In the projectile insertion station 27, a projectile 11 is inserted into the shell 2 which has already been filled with propellant 10.

The projectile insertion station 27 comprises a measurement subsystem 13 which is configured as a cartridge length measurement apparatus 28. The cartridge length measurement apparatus 28 outputs as measurement signal 15 a representation of the actual length L of the cartridge 3.

The projectile insertion station 27 further comprises, as an actuator subsystem 8, a press-in subsystem 29. In the press-in subsystem 29, a projectile is delivered to, and pressed into the cartridge 3 with the help of an actuator 14. The actuator 14 may be force-controlled or path-controlled and terminate the press-in process once a target force or a target stroke has been reached.

The projectile insertion station 27 further comprises a control subsystem 13 which is adapted to control the force and/or the stroke of the press-in subsystem 29 depending on a deviation of the actual cartridge length L as measured by the cartridge measurement device 28 from the target value T, here a target length L_(T), stored in the storage member 22 of the control subsystem 13 of the projectile insertion station 27. If, for example, the cartridges 3 produced by the press-in subsystem 29 are too short, the control subsystem 13 may modify the stroke of the actuator so that the projectiles 11 are pressed to a lesser degree into the shells 2 than before.

Again, the deviation from a single measurement or from an average formed by a multitude of subsequent measurements can be taken to control the actuator subsystem 8. The various control signals and lines are designated with the reference numeral 30 in FIG. 1.

It is to be understood that each of the above-described steps of adding a component 9, measuring a physical property P of the cartridge 3, and rejecting a cartridge 3 are performed during a working cycle of the conveyor subsystem.

Starting from the above generic representation of the automated progressive ammunition assembly apparatus 1 and method, further designs and functions are described with reference to the remaining figures.

FIG. 2 shows a schematic perspective view of an automated progressive ammunition assembly apparatus 1. The apparatus 1 has a powder reservoir 39 and a reservoir 40 for the shells which preferably are already equipped with the primer.

As can be seen in FIG. 2, the conveyor subsystem 4 comprises a conveyor belt 41 which extends rectilinearly in the assembly direction 6 through the apparatus 1. Along the conveyor belt 41, the assembly 5 stations are lined up rectilinearly in the assembly direction 6. Again, each assembly station 5 completes one assembly step. For each assembly step, there is exact one assembly station 5.

The conveyor belt 41 is provided with compartments 42. Each compartment 42 is adapted to receive loosely a single cartridge 3 in a standing position. The bottom 43 of the cartridge 3 slides on a transport plane 44 of the apparatus 1. Thus, the cartridges 3 are simply pushed by the conveyor belt 41 in the assembly direction 6. Each compartment 42 is separated from the neighboring compartments 42 in the assembly direction 6 by a vertical rib 45. The conveyor belt 41 and the ribs 45 are preferably made from rubber and/or resin material. Vertically, the compartments 42 are open, preferably such that a shell 2 may fall through a compartment 42. Each compartment 42 defines a niche-shaped receptacle for a cartridge 3.

The conveyor belt 41 may be vertically spaced apart from the transport plane 44 so that the cartridges 3 project both vertically beneath and above the conveyor belt 41. The compartments 42 surround each cartridge 3 an three sides only, namely both in and against the assembly direction 6, and both perpendicular to the assembly direction 6 and perpendicular to a longitudinal axis 46 of the cartridges 3 standing on the transport plane 44. This can be seen in FIG. 3.

To avoid wear of the transport plane 44, a stationary slider bar 47 made from hardened and polished steel may be located in the transport plane 44 underneath the conveyor belt 41. The slider bar 47 may be exchanged if worn.

As shown in FIG. 3, at least one stationary retainer bar 48 may be used which extends parallel to the conveyor belt 41 to keep the cartridges 3 in the respective compartments, facing and closing the compartments 42. The retainer bar 48 is preferably located at a short distance from the conveyor belt, so that no pressure or friction-generating force is generated between the cartridges 3, the conveyor belt 41, and the retainer bar 48 during transport of the cartridges 3 in the assembly direction 6. The distance 49 between the retainer bar 48 and the conveyor belt 41 is small enough to prevent the cartridges from being moved out of the compartments. The distance 49 is preferably smaller than half the outer width D_(S) of the shells 2, preferably even less than ¼ of the outer width D_(S).

The slider bar 47 and the retainer bar 48 may be combined monolithically to form a U- or L-shaped profile for guiding the cartridges 3 an at least two sides.

In the conveyor subsystem 4, the conveyor belt 41 is looped endlessly around two pulleys 50 of which the axes 51 are oriented vertically, i.e. parallel to the longitudinal axis 46 of the upright cartridges 3 in the conveyor belt 41. The loop 55 of the conveyor belt 41 defines a plane 56 which extends parallel to the transport plane 44 respectively.

It is to be noted that a drive 57 of the conveyor subsystem 4 is located above the transport plane 44. Thus, no openings are needed which extend through the transport plane 44 and in which the powdery propellant may gather during longer operations of the apparatus 1.

In the embodiment of FIG. 2, in a first step, the shells 2 which already may have been provided with a primer are fed and placed into the compartments 42 of the conveyor belt 41. This is done in a shell-feeding station 58. There, a feeder tube 59 may be extended from a shell reservoir 40 downwards to the location where a compartment 42 comes to rest between two subsequent transport cycles of the conveyor subsystem 4.

The shells 2 are fed through the feeder tube 59 passively by the force of gravity, and simply fall into the compartment 42. To allow this, the inner width D_(C) of a compartment 42 should be larger than the largest outer width D_(S) of the shell.

The feeding rhythm of the shell feeding station 58 is synchronized with the intermittent motion of the conveyor subsystem 4.

The shells 2 are then transported in the assembly direction 6 along a straight path to the powder filling station 18. There, the net weighing apparatus 20 a determines the weight W_(N) of each shell 2. The weight W_(N) may be stored in the control subsystem 13 of the powder filling station 18 and/or in the representation of the assembly process in the storage and control system 24 of the apparatus 1.

The shells 2 are then transported to the filler subsystem 19, where powder in a dosed amount is filled into the shells. From there, the shells are transported in the assembly direction 6 to the gross weighing apparatus 20 b, in which the weight W_(G) of the powder-filled shell 2 is determined. The weight W_(N) may be stored in the powder filling station 18 or in the storage and control subsystem 24.

In order to determine the actual weight of the amount of powder in the shell 2, the previously measured net weight W_(N) from the net weighing apparatus 20 a is subtracted from the gross weight W_(G) as measured by the gross weighing apparatus 20 b. The resulting weight difference W_(G)-W_(N) is then, as described above, compared to a target weight W_(T) and the dosing mechanism 21 of the powder filling 18 is adjusted correspondingly in a feedback loop control.

The powder-filled shells 2 may pass an optional reject station 23, which removes shells 2 with a powder filling that does not meet the specification for the particular cartridge 3 to be manufactured. This reject station 23 may be omitted if, as described above, the conveyor control subsystem 24 keeps track of all the cartridges currently in the assembly process.

The powder-filled shells 2 are then transported in the assembly direction 6 to a projectile insertion station 27. In the projectile insertion station 27, projectiles (not shown) are fed from a projectile reservoir 60 to a location, where the powder-filled shells 2 come to rest between two subsequent transport cycles of the conveyor subsystem 4. If the cartridge below the projectile insertion station 27 is marked in the storage and control subsystem 24 as containing a non-reject powder-filled shell which should be provided with a projectile, the projectile insertion station 27 presses a projectile into the powder-filled shell.

In the assembly direction 6 preferably immediately behind the projectile insertion station 27, a cartridge length measurement apparatus 28 may be located. The cartridge length measurement apparatus 28 determines the length L of the cartridge 3 with the pressed-in projectile. This actual length is then compared to a target length L_(T) as required by the specification for the cartridge 3 to be manufactured. If there is a deviation from the target value, the stroke of the projectile insertion station 27 is adjusted to compensate this deviation, as explained above.

Cartridges 3 which are either too long or too short to meet the specification may be removed from the conveyor subsystem 4 by a reject station 23 which is located downstream of the projectile insertion station 27. They may be marked as reject in the storage and control subsection 24 by setting the reject flag R for that particular cartridge 3.

A crimp station 65 may be provided, where the shell is crimped onto the projectile 11. The crimp station 65 may be located as shown between the projectile insertion station 27 and the length measurement apparatus 28.

Alternatively or additionally, another length measurement apparatus 28 may be located in the assembly direction 6 behind the crimp station 65 to control whether the length requirement is satisfied by the crimped cartridge 3. If the crimping process affects the length L of the cartridge 3, this may be compensated by adjusting the insertion stroke in the projectile insertion station 27. A difference can be calculated between the length L of the cartridge 3 before crimping and alter crimping in order to separate the effects of projectile Insertion from the effects of crimping and to provide adequate feedback control of the projectile insertion station 27 for both instances.

As can be seen in FIG. 2, all stations and subsystems are arranged above the transport plane 44 of the apparatus 1 or system 24 respectively. The apparatus 1 may comprise a dust-tight bulkhead 66 which separates a manufacturing space 67 from a bottom space 68. The bulkhead 66 may be formed by a massive steel or a metal sheet plate. Only the weighing apparatus 20 a, 20 b, notably its frame, may in one embodiment extend below the transport plane 44. The bulkhead 66 is spaced at a distance 61 from the transport plane so that the assembly stations 5 and all subsystems of the apparatus 1 are mounted on a mounting plane 62 of the apparatus 1.

The mounting plane 62 extends perpendicular to and above the bulkhead 66. Between the assembly stations 5 and the other subsystems of the apparatus 1 and the bulkhead 66 there is preferably an empty space 63 to allow easy access to the bulkhead 66 e.g. for cleaning. Only the weighing apparatus may extend into the empty space if a separated socket 100 for decoupling the weighing apparatus from the rest of the apparatus 1 is needed.

Next, the structure and function of a weighing apparatus 20 a, 20 b is explained with reference to FIGS. 4 to 6. The following description applies to both a net weighing apparatus 20 a and a gross weighing apparatus 20 b, which may be configured identically.

The weighing apparatus 20 a, 20 b comprises a weighing cell 69 which occupies the base area of a compartment 42. A bottom plate 70 of the weighing cell 69 is aligned flush with the transport plane 44. For weighing, a shell 2 is simply slid from the slider bar 47, which is provided with an opening or which is interrupted at this position, onto the bottom plate 70 during a transport cycle.

A transport channel 64 which is formed by the slider bar 47 and the retainer bar 48, which are monolithically combined and through which the shells 2 are transported, is clearly visible in FIG. 4.

For an accurate measurement of the weight, it is important that the shell 2 does not contact the compartment 42 or any other part of the apparatus 1, such as the slider bar 47 or the retainer bar 48, which does not belong to the weighing apparatus 20 a, 20 b. For this, a centering mechanism 71 is provided, which automatically moves the shell 2 away from contact with the compartment 42 and preferably centers the shell 2 an the bottom plate 70 of the weighing cell without moving the cartridge out of the compartment 42. This is preferably done automatically and passively, i.e. without any actuators requiring external power, during a transport cycle. The centering mechanism 71 may comprise a spring drive 72, which is automatically loaded and operated by the shell 2 being trans-ported onto the weighing cell 69.

In the embodiment of FIGS. 3 and 4, the spring drive 72 comprises at least one spring arm 73 which is adapted to be resiliently deflected in a direction parallel to the transport plane 44 and perpendicular to the assembly direction 6 by the shell 2 upon its transport onto the weighing cell 69. The spring arm 73 may be configured to be bent elastically upon deflection or be hinged using spring-loaded joints. The spring arm 73 is provided with a centering bevel 74, which may be V- or U-shaped in a cross-section parallel to the bottom plane. The bottom 75, where the width of the centering bevel 74 is widest, is located vertically above the center of the bottom plate 70. The bottom 75 may be rounded and in particular be formed complementary to the shell 2 to allow a snug fit.

One or two pairs of spring arms 73 may be provided on the opposite sides of the conveyor belt 41 and each of the spring arms may be provided with a centering bevel 74. The conveyor belt 41 may extend between each pair of spring arms 73. An upper pair 76 of spring arms may be adapted to engage a neck 77 of a shell 2, another, lower, pair 78 of spring arms may be adapted to engage the shell at its base shortly above the lower rim 79 of the shell 2.

The weighing cell 69 and the centering mechanism 71 operate as follows.

If, in a transport cycle of the conveyor subsystem 4, a shell 2 is pushed from the previous resting position 81 onto the weighing cell 69, the spring arms 73 are pried apart from each other by the shell 2 and thus generate a force which tries to move the spring arms 73 back towards each other. To allow easy entrance of the shell 2 into the centering bevel 74 between the spring arms 73, an entry bevel 82 may be provided, which provides an entrance opening 83 which opens wide against the assembly direction 6 and, in the assembly direction 6, narrows until the centering bevel 74 be-gins.

Once the shell 2 has moved past the entry bevel 82 and enters the centering bevel 74, the force exerted by the pried-open spring arms 73 pushes the shell automatically into the bottom 75, where the centering bevel 74 has its largest inner width. This happens in a quick snapping motion of the spring arms 73.

In the bottom 75 of the centering bevel 74, the shell is held spaced apart from the compartment 42 when the conveyor subsystem 4 has reached the next working cycle. For this, the weighing cell 69 with the at least one spring arm 73 has to be aligned with the resting position 81 of the compartment 42 on the location of the weighing cell 69.

With the shell 2 resting in the bottom 75 of the centering mechanism 71, the weight measurement can take place during the working cycle of the conveyor subsystem 4. As the spring arms 73 are part of the weighing cell 69, they do not falsify the weight measurement.

In the next transport cycle, the conveyor belt 41 first moves until it abuts the shell 2 at its surface facing away from the assembly direction 6. It then continues to push the shell 2 from the weighing cell 69 and out of the centering mechanism 71 by, again, prying apart the spring arms 73. To allow a smooth exit of the shell 2 from the centering mechanism 71, an exit bevel 84 may be provided which has an exit opening 85 that widens in the assembly direction 6. The geometry of the exit bevel 84 may be the same as for the entry bevel 82, except that directions are reversed.

To allow a smooth transition from the entry bevel 82 or the exit bevel 84 into the centering bevel 74, the transition zone between the two may be rounded.

Both the net weighing apparatus 20 a and the gross weighing apparatus 20 b acquire, during the same working cycle, the weight of two different shells 2. At the same time, another shell may be filled with powder. In order to determine the actual powder weight of a shell 2, only the net weight and the gross weight of one particular shell may be considered. This is facilitated by using the representation 26 of the current manufacturing process in the control and storage subsystem 24.

In FIG. 7, part of the powder filling station 18 is shown. The dosing mechanism 21 of the powder filling station 18 comprises an outer centering tube 86 with an inner centering bevel 87, and an inner feeder tube 88. The centering tube 86 and the feeder tube 88 are aligned coaxially and may be rigidly connected so that they are moved together. In the shown embodiment, however, the feeder tube 88 is stationary with respect to the shell 2 and the centering tube 86 may be moved independently of the feeder tube 88 in the vertical direction.

For filling a shell 2 with propellant 10, the centering tube 86 is moved vertically, until the centering bevel 87 hits an upper rim 89 of the shell in the compartment 42 underneath the dosing mechanism 21. The centering bevel 87 automatically centers the shell underneath the centering tube 86. For this, an outer diameter D_(BO) of the centering bevel 87 may be larger than the inner width D_(C) of the compartment. An inner diameter D_(BI) of the centering bevel 87 corresponds to the outer width D_(S) of the shell 2 so that the centering tube 86 may slide over the shell 2 and provide a dust-tight sealing during the filling process. Of course, it is also possible that the outer diameter of the centering tube 86 and the centering bevel 87 respectively correspond to an inner diameter of the shell 2, so that the centering tube 86 may slightly enter the shell.

Once the shell 2 is inserted in the centering tube 86 and thus centered within the compartment 42, the propellant 10 is falling through the feeder tube 88 into the shell 2.

The amount of propellant 10 is determined by the size of a dosing chamber 90. The size of the dosing chamber 90 is adjusted by the dosing mechanism 21 which uses a stepper motor 91 to move one wall 92 of the dosing chamber 21. The stepper motor 91 is moved together with the dosing chamber 90 in a reciprocating motion 93 which motion successively aligns the dosing chamber 90 with the powder reservoir 39 for filling and with the feeder tube 88 for discharging the powder into the shell 2. The size of the dosing chamber 90 is adjusted as described above depending on the values W_(N), W_(O) and W_(T).

In FIG. 8, a system 110 is shown consisting of two apparatuses 1, which are paired together side-by-side having parallel assembly directions.

The system 110 is easily scalable in its output and versatility, because the layout of the apparatus 1 allows to simply group two or more apparatuses 1 together in parallel. In the system 110, several apparatuses 1 may share a common powder reservoir 39, a common shell reservoir 40 and/or a common projectile reservoir 60. The assembly direction 6 is preferably the same so that the assembly stations 5 are at the same locations with respect to the assembly direction 6 in the parallel apparatus 1. The apparatus 1 may be arranged such that the transport planes 44 are at the same distance from the bulkhead 66.

FIG. 9 depicts a further preferred embodiment of the apparatus 1 according to invention for the manufacturing of ammunition. The apparatus 1 depicted in FIG. 9 corresponds to the preferred embodiment of an apparatus depicted in FIG. 2, illustrates however an alternative mounting of the assembly stations 5 as well as the conveyer system 4 to the mounting plane 62 of the apparatus 1. The working principle for the apparatus 1 is the same as detailed for the apparatus depicted in FIG. 2. Shells 2 are supplied from the shell reservoir 40 into compartments 42 of the conveyer belt 41. In the powder filling station 18 the ammunition powder is filled into the shells 2. The amount of powder is controlled by means of a feedback control mechanism that is based on the weight measurements of the shell 2 prior to and after the powder dosing using the weighting apparatus 20 a and 20 b. Subsequently the cartridges 3 are moved along the sectionwise linear conveyer belt 41 and are worked upon by additional assembly stations 5 that are arranged in a rectilinear manner along the assembly direction 6. The projectile insertion station 27 serves to press the projectiles 11 into the shells 2. To this end the projectiles 11 are preset into the shells 2 and subsequently pressed-in using the press-in subsystem 29. By means of a cartridge length measurement apparatus 28 the projectile insertion can be monitored and adapted by a feedback control. As shown in FIG. 9 the assembly stations 5 as well as the conveyer system 4 are attached to the mounting plane 62 such that an empty space 63 is formed between these components of the apparatus 1 and the upper surface of the horizontal bulk head 66. The assembly stations 5 and the conveyer system 4 are therefore situated in a manufacturing space 67 above the bottom space of the apparatus 68. The horizontal bulk head 66 may be preferably made of metal and is preferably constructed in a dust-tight manner: Only the weighing apparatus 20 a and 20 b may extend into the bottom space 68. However the weighting cells 69 are also concealed in a dust-tight manner. In the preferred embodiment ammunition powder will remain on the upper surface of the bulk head 66 and can be easily removed due to the empty space 63. The attachment of the assembly stations 5 to the mounting plane 62 allows for a fast mounting and demounting of the assembly stations 5. The preferred embodiment of the apparatus 1 is therefore characterized by a modular design allowing for a high degree of functional flexibility.

FIG. 10 shows a schematic view of a further preferred measurement subsystem 12 for measuring the weight of a cartridge comprising a rotatable transport device. In FIG. 10 two measurement subsystems 12 are shown side-by-side as it is preferably the case for two conveyor subsystems 4 arranged side-by-side for a system of two apparatus assembled parallel and next to each. However, the illustrated mechanism of the preferred measurement subsystem 12 comprising a rotatable transport device 121 equally applies to an apparatus 1 with a single conveyor subsystem 4. In the preferred embodiment the conveyor subsystem 4 comprises a conveyor belt 41 comprising compartment 42 to receive the shells 2 which are separated by vertical ribs 45. The shells 2 are moved through the apparatus by means of said conveyor belt 41 pushing the shells 2 within a transport guide 48. As explained with respect to FIG. 4-6 in one embodiment of the invention the weighing cells 69 are installed in line with the conveyor subsystem 4, wherein it is preferred to use a centering apparatus to allow to separate the cartridges from the conveyor subsystem 4 in order to arrive at more precise weight measurements. FIG. 9 depicts a particularly preferred alternative solution to arrive at a highly precise weight measurement. Instead of installing the weighing cells 69 in line with the conveyor subsystem 4, i.e. in line with the conveyor belt 41 and the transport guide 48. The embodiment of the weighing apparatus 20 a, 20 b of FIG. 10 comprises weighing cells 69, whose measurement position is outside the conveyor belt 41. In order to move the shells 2 from the conveyor belt 41 to the respective weighing cell 69, the measurement subsystem 12 comprises a transport device 121, which is preferably rotatable. It is particularly preferred that the rotatable transport device 121 comprise a lower transport wheel 123 and an upper transport wheel 122 that comprise niches or compartments shaped to receive the shells 2. In a preferred embodiment the weighing procedure is conducted as follows.

The shells 2 are transported within the transport guide 48 by means of the conveyor belt 41 towards the transport device 121 comprising rotatable upper and lower transport wheels 123, 122. The rotation of the transport wheels 122, 123 is synchronized with the movement of the conveyor belt 41 such that a single shell 2 passes from one of the compartments 42 of the conveyor belt 41 to a corresponding compartment of the transport wheels 122, 123. As it is the case for the linear movement of the conveyor belt 41 the rotation of the transport wheels 122, 123 is preferably intermittently comprising a transport and a working cycle. By means of the intermittent rotation the shells 2 are moved on top of a transportation plane towards a first weighing cell 69 of the net weighing apparatus 20 a. It is preferred that the weighing cell 69 is not mechanically connected to the conveyor subsystem 4. For instance the conveyor subsystem 4 may be mounted to a base frame or mounting plane (not shown in FIG. 10), while the weighing cells 69 is situated on top of a support 120, which is mounted on a free standing socket 100. Thereby it can be efficiently avoided to transmit vibrations of the conveyor subsystem 4 or base frame to the weighing apparatus.

To this end it is particularly preferred that after the shell 2 is moved onto the measurement position of the weighing cell 69 the transport device 121 is rotated slightly backwards in order to ensure that during the measurement the shell 2 is not in contact with the transport wheels 122, 123. This procedure proved to allow for a particular precise measurement of the net weight of the shells 2. After the measurement the transport device 121 continuous to move the shells 2 towards a position for the filling of ammunition powder. At this position the filler subsystem (not shown in FIG. 10) of the powder filling station adds the ammunition powder to the shell 2. Subsequently the transport wheels 122, 123 continue to move the shell 2 filled with ammunition powder towards a second weighing cell 69 of the gross weighing apparatus 20 b. It is likewise preferred that prior to the gross weight measurement the transport wheels 122, 123 are moved slightly backward in order to ensure a precise measurement that is not compromised by the shells 2 touching the transport wheels 122, 123. Throughout the operation of the apparatus the transport wheels 122, 123 hence perform an intermittent rotation along the rotation direction with a transport and working cycle, wherein before the working cycle (and thus a measurement) starts the rotation is shortly reverted. Afterwards the shells 2 are further moved along by means of the rotating transport device 121 and handed back over to the conveyor belt 41 and transport guide 41 to continue the processing along the assembly line.

It is preferred that the rotation of the transport wheels is achieved by means of a servo motor allowing for a particular precise motion. Moreover as seen in FIG. 10 it is particular preferred that each of the weighing cells 69 are installed on separate supports 120 which may be mounted onto a common socket for the weighing apparatus 20 a, 20 b. In case of an embodiment with two conveyor subsystems 4, the four weighing cells 69 of the two net weighing apparatus 20 a and two gross weighing apparatus 20 b are preferable installed onto the same socket 100. It is preferred that said socket 100 is mechanically disconnected from the rest of the base frame for the apparatus, which may as previously described comprise a bulkhead and a mounting plane (not shown in FIG. 10).

REFERENCE NUMERALS

-   1 automated progressive ammunition assembly apparatus -   2 shell -   3 cartridge -   4 conveyor subsystem -   5 assembly station -   6 assembly direction -   8 actuator subsystem -   9 component -   10 propellant/powder -   11 projectile -   12 measurement subsystem -   13 control subsystem -   14 actuator -   15 measurement signal -   18 powder filling station -   19 filler subsystem -   20 a net weighing apparatus -   20 b gross weighing apparatus -   21 dosing mechanism -   22 storage member of control subsystem -   23 reject station -   24 storage and control subsystem -   25 storage section of conveyor control subsystem -   26 representation of cartridges presently in storage section of the     conveyor subsystem -   27 projectile insertion station -   28 cartridge length measurement apparatus -   29 press-in subsystem -   30 control signals -   39 powder reservoir -   40 shell reservoir -   41 conveyor belt -   42 compartment of conveyor belt -   43 bottom of cartridge or shell -   44 transport plane an which cartridges stand upright during     transport -   45 ribs between compartments -   46 longitudinal axis of cartridge -   47 slider bar -   48 retainer bar -   49 distance between retainer bar and conveyor belt -   50 pulley for conveyor belt -   51 axis of pulley -   55 loop of conveyor belt -   56 plane of conveyor belt loop -   57 drive of conveyor subsystem -   58 shell feeding station -   59 feeder tube -   60 projectile reservoir -   61 distance between transport plane and bulkhead -   62 mounting plane -   63 empty space -   64 transport channel -   65 crimp station -   66 dust-tight bulkhead -   67 manufacturing space of apparatus -   68 bottom space of apparatus -   69 weighing cell -   70 bottom plate of weighing cell -   71 centering mechanism of weighing cell -   72 spring drive -   73 spring arm -   74 centering bevel of centering mechanism -   75 bottom of centering bevel -   76 upper pair of spring arms -   77 neck of shell -   78 lower pair of spring arms -   79 rim of the primer -   80 primer of cartridge -   81 resting position -   82 entry bevel of centering mechanism -   83 entrance opening of entry bevel -   84 exit bevel of centering mechanism -   85 exit opening of exit bevel -   86 centering tube -   87 inner centering bevel of centering tube -   88 feeder tube -   89 upper rim of shell -   90 dosing chamber -   91 stepper motor -   92 wall of dosing chamber -   93 reciprocating motion -   100 socket of weighing apparatuses -   110 system comprising at least two apparatuses -   120 support for weighing cells -   121 transport device -   122 upper transport wheel -   123 lower transport wheel -   124 servo motor for the transport device -   D_(C) inner width of compartment -   D_(S) outer width of shell -   D_(BI) inner width of centering bevel of centering tube -   D_(BO) outer width of centering bevel of centering tube -   L_(T) target length of the cartridge -   L measured length of the cartridge -   ID identification number of the cartridge -   P physical parameter of cartridge -   R reject flag -   target value -   W weight -   W_(G) gross weight -   W_(N) net weight -   W_(T) target weight 

1. Automated progressive ammunition, in particular cartridge, assembly apparatus (1) comprising a conveyor subsystem (4) and at least one assembly station (5), the at least one assembly station comprising an actuator subsystem (8), a measurement subsystem(12) and a control subsystem (13), the conveyor subsystem (4) being adapted to transport ammunition (2, 3) past the at least one assembly station in an assembly direction (6), the actuator subsystem (8) being adapted to add a component (9) to the ammunition, the component changing at least one physical parameter (P) of the ammunition, the measurement subsystem (12) being adapted to measure the at least one physical parameter and output a measurement signal (15) representative of the at least one measured physical parameter, wherein the control subsystem (13) is adapted to control the actuator subsystem (8) depending on the measurement signal.
 2. Automated progressive ammunition assembly apparatus (1) according to claim 1, wherein the control subsystem (13) comprises a storage member (22) in which a representation of at least one target physical parameter (T) is retained and wherein the control subsystem (13) is adapted to control the actuator subsystem (8) depending on a deviation of the at least one measured physical parameter (P) from the at least one target physical parameter.
 3. Automated progressive ammunition assembly apparatus (1) according to any one of claim 1 or 2 wherein the conveyer subsystem (4) comprises a conveyer belt (41) comprising compartments (42) configured to receive the ammunition (2,3) and the conveyer belt (41) extends at least sectionwise linearly to transport the ammunition past the at least one assembly station (5).
 4. Automated progressive ammunition assembly apparatus (1) according to the previous claim, wherein the conveyer subsystem (4) is assembled as a loop (55) around two pulleys (50), which lie on an axis and are rotated by means of a driver (57).
 5. Automated progressive ammunition assembly apparatus (1) according to any one of claims 1 to 4, wherein the at least one assembly station (5) is a powder filling station (18).
 6. Automated progressive ammunition assembly apparatus (1) according to any one of claims 1 to 5, wherein the component (9) is a propellant (10) and wherein the at least one physical parameter (P) is powder weight (W) in the cartridge (2, 3).
 7. Automated progressive ammunition assembly apparatus (1) according to any one of the previous claims, wherein the measurement subsystem (12) comprises a net weighing apparatus (20 a) which is arranged in the assembly direction (6) before the actuator subsystem (8) and a gross weighing apparatus (20 b) which is arranged in the assembly direction (6) behind the actuator subsystem (8).
 8. Automated progressive ammunition assembly apparatus (1) according to any one of the previous claims, wherein the measurement subsystem (12) comprises a weighing apparatus (20 a, 20 b) which has a weighing cell (69) that is arranged in line with the conveyor subsystem (4).
 9. Automated progressive ammunition assembly apparatus (1) according to the previous claim, wherein the weighing cell (69) is mounted flush to a transport plane (44) an which the ammunition (2, 3) stands while being pushed by the conveyor subsystem (4).
 10. Automated progressive ammunition assembly apparatus (1) according to claim 8 or 9, wherein the weighing cell (69) comprises a centering mechanism (71) which is adapted to move automatically the ammunition (2, 3) away from contact with the conveyor subsystem (4) upon transport of the ammunition (2,3) onto the weighing cell (69).
 11. Automated progressive ammunition assembly apparatus (1) according to claim 10, wherein the centering apparatus (71) comprises a spring drive (72) with at least one centering bevel (74), the spring drive being adapted to be automatically loaded by the ammunition (2, 3) transported by the conveyor subsystem (4) onto the weighing cell (69).
 12. Automated progressive ammunition assembly apparatus (1) according to claim 10 or 11, wherein the centering apparatus (71) comprises a spring drive (72) with at least one centering bevel (74), in which the ammunition (2,3) is held spaced apart from conveyor subsystem (4) during a working cycle of the conveyor subsystem (4).
 13. Automated progressive ammunition assembly apparatus (1) according to any one of the previous claims, wherein the measurement subsystem (12) comprises a weighing apparatus (20 a, 20 b) comprising a weighing cell (69) and the apparatus comprises a transport device (120) adapted to separate the ammunition (2,3) from the conveyor subsystem (4) in order to pass them onto the weighing cell (69).
 14. Automated progressive ammunition assembly apparatus (1) according to the previous claim, wherein conveyor subsystem (4) comprises a conveyor belt (41) configured to transport the ammunition (2,3) within compartments (42) and the transport device (120) comprises at least one transport wheel (122, 123) adapted to receive the ammunition (2, 3) from said compartments (42) and transport the ammunition (2,3) onto the weighing cell.
 15. Automated progressive ammunition assembly apparatus (1) according to any one of the previous claims, which apparatus (1) comprises a projectile insertion station (27), the component (9) is a projectile (11) and the at least one physical parameter (P) is a length (L) of a cartridge (3) with an inserted projectile (11).
 16. Automated progressive ammunition assembly apparatus (1) according to any one of the previous claims, which apparatus (1) comprises a plurality of assembly stations (5), wherein the conveyor subsystem (4) extends linearly at least sectionwise through the automated progressive ammunition assembly apparatus (1) and the assembly stations (5) are arranged rectilinearly one behind the other in the assembly direction (6).
 17. Automated progressive ammunition assembly apparatus (1) according to any one of the previous claims, which apparatus (1) further comprises a horizontal bulkhead (66) which separates an upper manufacturing space (67), in which the conveyor subsystem (4) and at least one assembly station (5) are arranged, from a lower bottom space (68) in a dust-tight manner.
 18. Automated progressive ammunition assembly system (110) comprising at least two automated progressive ammunition assembly apparatuses (1) according to any one of claims 1 to 17, wherein the conveyor subsystems (4) of the apparatuses are arranged parallel and side-by-side and wherein at least one assembly station (5) of one automated progressive ammunition assembly apparatus (1) shares at least one reservoir (39, 90, 91) with an adjacent automated progressive ammunition assembly apparatus (1).
 19. Automated progressive ammunition, in particular cartridge, assembly method comprising the steps of adding a component (9) to the ammunition (2, 3) thereby changing a physical parameter (P) of the ammunition (2,3), of automatically measuring the physical parameter and of automatically modifying the addition of the component depending on the measured physical parameter. 